There are needs in this art to be able to supply liquid, as a rule water and/or cleaning liquid, to a bathtub in immediate association with the upper edge of the bathtub. In certain practical applications, the term cleaning liquid is taken to signify also liquid including disinfectant agents. Since the liquid is supplied in immediate association with the upper edge of the tub, complete cleaning of the tub will be facilitated, i.e. cleaning of all regions of the tub into which the bather may come into contact, or with which the bathing water may come into contact. In a medical care context, such a complete cleaning is a regularly recurring need. A distribution of the liquid supply such that this takes place along all parts of the upper edge of the tub also affords the advantage that, at peak working periods, cleaning of the bathtub may be postponed without the dirt/impurities coagulating on the surface of the bath, since there is the possibility of supplying liquid to the bathtub from time to time, thereby keeping the dirt/impurities damp. In order to achieve the above disclosed effects, it is necessary that the liquid be supplied in a uniform flow which covers all parts of the inner defining surface of the bathtub, so that the liquid, while on its passage towards the bottom and outlet of the tub, wets all parts of the inner surface of the bathtub.
For economic reasons, it is desirable that an apparatus for cleaning bathtubs supplies the cleaning liquid to the tub substantially fully automatically--as far as this is possible--and makes optimum use of the supplied cleaning liquid. Optimum utilization of the cleaning liquid requires that during each cleaning period only a minor volume of cleaning liquid is utilized, whereby contemplated environmental advantages will also be attained. In addition, it is necessary that the apparatus empties the bath of cleaning liquid and rinses the bath before the bath water is run into the bath.